One size doesn't fit all: Research methodologies in a language variation study of Sudanese teens

The research reported here draws on a study of five teenagers from a Dinka-speaking community of Sudanese settling in Australia. A range of factors including language proficiency, social network structure and language attitudes are examined as possible causes for the variability of language use. The results and discussion illustrate how the use of a triangular research approach captured the complexity of the participants' language situation and was critical to developing a full understanding of the interplay of factors influencing the teens' language maintenance and shift in a way that no single method could. Further, it shows that employment of different methodologies allowed for flexibility in data collection to ensure the fullest response from participants. Overall, this research suggests that for studies of non-standard communities, variability in research methods may prove more of a strength that the use of standardised instruments and approaches.

It's all very well, in theory: Theoretical perspectives and their applications in contemporary pedagogical research

Current debates about educational theory are concerned with the relationship between knowledge and power and thereby issues such as who possesses a truth and how have they arrived at it, what questions are important to ask, and how should they best be answered. As such, these debates revolve around questions of preferred, appropriate, and useful theoretical perspectives. This paper overviews the key theoretical perspectives that are currently used in physical education pedagogy research and considers how these inform the questions we ask and shapes the conduct of research. It also addresses what is contested with respect to these perspectives. The paper concludes with some cautions about allegiances to and use of theories in line with concerns for the applicability of educational research to pressing social issues.

A unified and complete construction of all finite dimensional irreducible representations of gl(2|2)

Representations of the non-semisimple superalgebra gl(2/2) in the standard basis are investigated by means of the vector coherent state method and boson-fermion realization. All finite-dimensional irreducible typical and atypical representations and lowest weight (indecomposable) Kac modules of gl(2/2) are constructed explicity through the explicit construction of all gl(2) circle plus gl(2) particle states (multiplets) in terms of boson and fermion creation operators in the super-Fock space. This gives a unified and complete treatment of finite-dimensional representations of gl(2/2) in explicit form, essential for the construction of primary fields of the corresponding current superalgebra at arbitrary level.

A PCR-based method of screening individuals of all ages, from neonates to the elderly, for familial hyperaldosteronism type I

Aim: Unless specifically treated (glucocorticoids in low doses), Familial Hyperaldosteronism Type I(FH-I) may result in early death from stroke. We report the successful application of a rapid, polymerase chain reaction (PCR)-based method of detecting the 'hybrid' 11 beta-hydroxylase (11 beta-OHase)/aldosterone synthase (AS) gene as a screening test for FH-I. Methods: 'Long-PCR' was used to amplify, concurrently, a 4 kb fragment of AS gene (both primers AS-specific) and a 4 kb fragment of the hybrid gene (5' primer 11 beta-OHase-specific, 3'primer AS-specific) from DNA extracted from blood either collected locally or transported from elsewhere. Sample collection and transport were straightforward. This 4 kb fragment contains all the currently recognised hybrid gene 'crossover' points. Results: Within a single family, long-PCR identified all 21 individuals known to have FH-I. Hypertension was corrected in all 11 treated with glucocorticoids. Nine with normal blood pressure are being closely followed for development of hypertension. Long-PCR cord blood analysis excluded FH-I in three neonates born to affected individuals. Long-PCR newly identified two other affected families: (1) a female (60 years) with a personal and family history of stroke and her normotensive daughter (40 years), and (2) a female (51 years) previously treated for primary aldosteronism with amiloride, her two hypertensive sons (14 and 16 years) and her hypertensive mother (78 years). No false negative or false positive results have yet been encountered. At least seven other centres have successfully performed this test. Conclusion: Long-PCR is a reliable method of screening individuals of all ages for FH-I.

Oxidation mechanism of Si3N4-bonded SiC ceramics by CO, CO2 and steam

This paper presents a theoretical and experimental investigation into the oxidation reactions of Si3N4-bonded SiC ceramics. Such ceramics which contain a small amount of silicon offer increased oxidation and wear resistance and are widely used as lining refractories in blast furnaces. The thermodynamics of oxidation reactions were studied using the JANAF tables. The weight gain was measured using a thermogravimetric analysis technique to study the kinetics. The temperature range of oxidation measurements is from 1073 to 1573 K and the oxidation atmosphere is water vapour, pure CO and CO-CO2 gas mixtures with various CO-to-CO2 ratios. Thermodynamic simulations showed that the oxidation mechanism of Si3N4-bonded SiC ceramics is passive oxidation and all components contribute to the formation of a silica film. The activated energies of the reactions follow the sequence Si3N4>SiC>Si. The kinetic study revealed that the oxidation of Si3N4-bonded SiC ceramics occurred in a mixed regime controlled by both interface reaction and diffusion through the silica film. Under the atmosphere conditions prevailing in the blast furnace, this ceramic is predicted to be passively oxidized with the chemical reaction rate becoming more dominant as the CO concentration increases. (C) 1998 Chapman & Hall.

The Australian mortality decline: all-cause mortality 1788-1990

This review describes the Australian decline in all-cause mortality, 1788-1990, and compares this with declines in Europe and North America. The period until the 1870s shows characteristic 'crisis mortality', attributable to epidemics of infectious disease. A decline in overall mortality is evident from 1880. A precipitous fall occurs in infant mortality from 1900, similar to that in European countries. Infant mortality continues downward during this century (except during the 1930s), with periods of accelerated decline during the 1940s (antibiotics) and early 1970s. Maternal mortality remains high until a precipitous fall in 1937 coinciding with the arrival of sulphonamide. Excess mortality due to the 1919 influenza epidemic is evident. Artefactual falls in mortality occur in 1930, and for men during the war of 1939-1945. Stagnation in overall mortality decline during the 1930s and 1945-1970 is evident for adult males, and during 1960-1970 for adult females. A decline in mortality is registered in both sexes from 1970, particularly in middle and older age groups, with narrowing of the sex differential. The mortality decline in Australia is broadly similar to those of the United Kingdom and several European countries, although an Australian advantage during last century and the first part of this century may have been due to less industrialisation, lower population density and better nutrition. Australia shows no war-related interruptions in the mortality decline. Australian mortality patterns from 1970 are also similar to those observed in North America and European countries (including the United Kingdom, but excluding Eastern Europe).

The HI Parkes All Sky Survey: southern observations, calibration and robust imaging

The acquisition of HI Parkes All Shy Survey (HIPASS) southern sky data commenced at the Australia Telescope National Facility's Parkes 64-m telescope in 1997 February, and was completed in 2000 March. HIPASS is the deepest HI survey yet of the sky south of declination +2 degrees, and is sensitive to emission out to 170 h(75)(-1) Mpc. The characteristic root mean square noise in the survey images is 13.3 mJy. This paper describes the survey observations, which comprise 23 020 eight-degree scans of 9-min duration, and details the techniques used to calibrate and image the data. The processing algorithms are successfully designed to be statistically robust to the presence of interference signals, and are particular to imaging point (or nearly point) sources. Specifically, a major improvement in image quality is obtained by designing a median-gridding algorithm which uses the median estimator in place of the mean estimator.

Health for all beyond 2000: the demise of the Alma-Ata Declaration and primary health care in developing countries

Access to basic health services was affirmed as a fundamental human right in the Declaration of Alma-Ata in 1978. The model formally adopted for providing healthcare services was primary health care (PHC), which involved universal, community-based preventive and curative services, with substantial community involvement. PHC,did not achieve its goals for several reasons, including the refusal of experts and politicians in developed countries to accept the principle that communities should plan and implement their own heathcare services. Changes in economic philosophy led to the replacement of PHC by Health Sector Reform, based on market forces and the economic benefits of better health. It is time to abandon economic ideology and determine the methods that will provide access to basic healthcare services for all people.

Combined in-fermenter extraction and cross-flow microfiltration for improved inclusion body processing

In this study we demonstrate a new in-fermenter chemical extraction procedure that degrades the cell wall of Escherichia coli and releases inclusion bodies (IBs) into the fermentation medium. We then prove that cross-flow microfiltration can be used to remove 91% of soluble contaminants from the released IBs. The extraction protocol, based on a combination of Triton X-100, EDTA, and intracellular T7 lysozyme, effectively released most of the intracellular soluble content without solubilising the IBs. Cross-flow microfiltration using a 0.2 mum ceramic membrane successfully recovered the granulocyte macrophagecolony stimulating factor (GM-CSF) IBs with removal of 91% of the soluble contaminants and virtually no loss of IBs to the permeate. The filtration efficiency, in terms of both flux and transmission, was significantly enhanced by infermenter Benzonase(R) digestion of nucleic acids following chemical extraction. Both the extraction and filtration methods exerted their efficacy directly on a crude fermentation broth, eliminating the need for cell recovery and re-suspension in buffer. The processes demonstrated here can all be performed using just a fermenter and a single cross-flow filtration unit, demonstrating a high level of process intensification. Furthermore, there is considerable scope to also use the microfiltration system to subsequently solubilise the IBs, to separate the denatured protein from cell debris, and to refold the protein using diafiltration. In this way refolded protein can potentially be obtained, in a relatively pure state, using only two unit operations. (C) 2004 Wiley Periodicals Inc.

Infrarenal aortic diameter predicts all-cause mortality

Objective - To assess the relationship between infrarenal aortic diameter and subsequent all-cause mortality in men aged 65 years or older. Methods and Results - Aortic diameter was measured using ultrasound in 12 203 men aged 65 to 83 years as part of a trial of screening for abdominal aortic aneurysms. A range of cardiovascular risk factors was also documented. Mortality over the next 3 to 7 years was assessed using record linkage. Initial aortic diameter was categorized into 10 intervals, and the relationship between increasing diameter and subsequent mortality was explored using Cox proportional hazard models. Median diameter increased from 21.4 mm in the youngest men to 22.1 mm in the oldest men. The cumulative all-cause mortality increased in a graded fashion with increasing aortic diameter. Using the diameter interval 19 to 22 mm as the reference, the adjusted hazard ratio for all-cause mortality increased from 1.26 (95% CI: 1.09, 1.44; P = 0.001) for aortic diameters of 23 to 26 mm to 2.38 (95% CI: 1.22, 4.61; P = 0.011) for aortic diameters of 47 to 50 mm. Analysis of causes of death indicated that cardiovascular disease was an important contributor to this increase. Conclusion - Infrarenal aortic diameter is an independent marker of subsequent all-cause mortality.

Thoracic aorta calcification detected by electron beam tomography predicts all-cause mortality

Background: The presence of coronary artery calcium (CAC) is an independent marker of increased risk of cardiovascular disease (CVD) events and mortality. However, the predictive value of thoracic aorta calcification (TAC), which can be additionally identified without further scanning during assessment of CAC, is unknown. Methods: We followed a cohort of 8401 asymptomatic individuals (mean age: 53 +/- 10 years, 69% men) undergoing cardiac risk factor evaluation and TAC and CAC testing with electron beam computed tomography. Multivariable Cox proportional hazards models were developed to predict all-cause mortality based on the presence of TAC. Results: During a median follow-up period of 5 years, 124 (1.5%) deaths were observed. Overall survival was 96.9% and 98.9% for those with and without detectable TAC, respectively (p < 0.0001). Compared to those with no TAC, the hazard ratio for mortality in the presence of TAC was 3.25 (95% CI: 2.28-4.65, p < 0.0001) in unadjusted analysis. After adjusting for age, gender, hypertension, dyslipidemia, diabetes mellitus, smoking and family history of premature coronary artery disease, and presence of CAC the relationship remained robust (HR 1.61, 95% CI: 1.10-2.27, p = 0.015). Likelihood ratio chi(2) statistics demonstrated that the addition of TAC contributed significantly in predicting mortality to traditional risk factors alone (chi(2) = 13.62, p = 0.002) as well as risk factors + CAC (chi(2) = 5.84, p = 0.02) models. Conclusion: In conclusion, the presence of TAC was associated with all-cause mortality in our study; this relationship was independent of conventional CVD risk factors as well as the presence of CAC. (C) 2009 Elsevier Ireland Ltd. All rights reserved.